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Title: Thermally Driven Electronic Topological Transition in FeTi

Abstract

In this paper, ab initio molecular dynamics, supported by inelastic neutron scattering and nuclear resonant inelastic x-ray scattering, showed an anomalous thermal softening of the M 5 - phonon mode in B2-ordered FeTi that could not be explained by phonon-phonon interactions or electron-phonon interactions calculated at low temperatures. A computational investigation showed that the Fermi surface undergoes a novel thermally driven electronic topological transition, in which new features of the Fermi surface arise at elevated temperatures. Finally, the thermally induced electronic topological transition causes an increased electronic screening for the atom displacements in the M 5 - phonon mode and an adiabatic electron-phonon interaction with an unusual temperature dependence.

Authors:
 [1];  [2];  [1];  [1];  [3];  [1];  [4];  [4];  [5];  [1]
  1. California Inst. of Technology (CalTech), Pasadena, CA (United States). Applied Physics and Materials Science Dept.
  2. California Inst. of Technology (CalTech), Pasadena, CA (United States). Applied Physics and Materials Science Dept.; The Datum Inst., Beaverton, OR (United States)
  3. California Inst. of Technology (CalTech), Pasadena, CA (United States). Applied Physics and Materials Science Dept.; Air Force Research Lab. (AFRL), Wright-Patterson AFB, OH (United States)
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Quantum Condensed Matter Division
  5. Carnegie Inst. of Washington, Argonne, IL (United States). Geophysical Lab., High Pressure Collaborative Access Team (HPCAT)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); California Inst. of Technology (CalTech), Pasadena, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1302899
Alternate Identifier(s):
OSTI ID: 1286302
Grant/Contract Number:
FG02-03ER46055; AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 117; Journal Issue: 7; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 36 MATERIALS SCIENCE

Citation Formats

Yang, F. C., Muñoz, J. A., Hellman, O., Mauger, L., Lucas, M. S., Tracy, S. J., Stone, M. B., Abernathy, D. L., Xiao, Yuming, and Fultz, B. Thermally Driven Electronic Topological Transition in FeTi. United States: N. p., 2016. Web. doi:10.1103/PhysRevLett.117.076402.
Yang, F. C., Muñoz, J. A., Hellman, O., Mauger, L., Lucas, M. S., Tracy, S. J., Stone, M. B., Abernathy, D. L., Xiao, Yuming, & Fultz, B. Thermally Driven Electronic Topological Transition in FeTi. United States. doi:10.1103/PhysRevLett.117.076402.
Yang, F. C., Muñoz, J. A., Hellman, O., Mauger, L., Lucas, M. S., Tracy, S. J., Stone, M. B., Abernathy, D. L., Xiao, Yuming, and Fultz, B. Mon . "Thermally Driven Electronic Topological Transition in FeTi". United States. doi:10.1103/PhysRevLett.117.076402. https://www.osti.gov/servlets/purl/1302899.
@article{osti_1302899,
title = {Thermally Driven Electronic Topological Transition in FeTi},
author = {Yang, F. C. and Muñoz, J. A. and Hellman, O. and Mauger, L. and Lucas, M. S. and Tracy, S. J. and Stone, M. B. and Abernathy, D. L. and Xiao, Yuming and Fultz, B.},
abstractNote = {In this paper, ab initio molecular dynamics, supported by inelastic neutron scattering and nuclear resonant inelastic x-ray scattering, showed an anomalous thermal softening of the M5- phonon mode in B2-ordered FeTi that could not be explained by phonon-phonon interactions or electron-phonon interactions calculated at low temperatures. A computational investigation showed that the Fermi surface undergoes a novel thermally driven electronic topological transition, in which new features of the Fermi surface arise at elevated temperatures. Finally, the thermally induced electronic topological transition causes an increased electronic screening for the atom displacements in the M5- phonon mode and an adiabatic electron-phonon interaction with an unusual temperature dependence.},
doi = {10.1103/PhysRevLett.117.076402},
journal = {Physical Review Letters},
number = 7,
volume = 117,
place = {United States},
year = {Mon Aug 08 00:00:00 EDT 2016},
month = {Mon Aug 08 00:00:00 EDT 2016}
}

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